Light projecting apparatus



Oct. 4, Y DODGE LIGHT PROJECTING APPARATUS Filed March 25, 1931 [)2van/02",. /a z'e/yfloafycw y @WM y 8.-

UNITED STATES mm Y. DODGE, OF SOUTH BEND, INDIANA LIGHT PBOJ'EGIINGApplication fled. larch 1931. Serial No. 524,525.

My invention relates to a light-projecting apparatus and moreparticularly to means which will provide greater efliciency in theprojection of light used in combination with a parabolic reflector.

In my construction, I have provided a means for supporting incombination or separately a refracting ens and shield m a predeterminedrelationship with an electric light bulb. The shield may be so treatedas to reflect and redirect certain rays of light into desired channels.

While this invention is especially applicable for use in combinationwith a lens such as is described and shown in my co pendmg application,Serial No. 449,198, filed May 2, 1930, or in my other co-pendmgapplicatlon, Serial No. 469,022, filed July 19, 1930, it may be usedwith any lens having related characteristics. It will also be noted thatwhile my invention may be used with many types of projectedillumination, it Is particularly well adapted for use with a typicalautomobile head lamp.

- It is well lmown in the art, that of the hght radiating from anelectric bulb, a very considerable portion does not reach the reflectorbut is emitted in a cone-shaped beam through the glass door of the headlamp. 7

36 It is self-evident that the rays of this bea which are projecting inan upward direction serve no useful purpose and may in certainatmospheric conditions reduce the roadvisibility to an important degree.

Now, a lens such as is shgawn and in m reviously-mention co-penapplicatidiis will admirably mrve to redirect the upwardly-inclined raysof light emitted from the bulb in a forward direction. It is also true,however, that in manufacturing lenses of this type, on an economicalbasis and in great quantities, aberrations are apt to occur in the glasswhich will aflect its refracting characteristics at certain points.

An object of my invention is to provide a construction which willredirect the rays which may have miscarried, due to aberrations in thelens.

A further object is to provide a construction which will render itpossible to remove or replace the lens and its shield, from or to, the 8tion on an enlarged scale, showing its relationship with a light bulbbut removed from the lamp casing and reflector;

3 is a vertical axial section of Fig. 2;

' Fig. 4 is a section on the line 44 of Fig. 3, with the light bulbremoved; I

Fig. 5 is an elevational view of a modified form of my invention;

Fig. 6 is a section on the line 6-6 of Fig. 5 with the light bulbremoved; and

Fig. 7 is a further modification of my device shown in side elevation.

Referring to the drawing in detail, the construction shown comprises ahead-light casing 1 having mounted within it a reflector 2 which isconstructed to retain in position the light bulb 3 when contained in itssocket 4. A- shield 5 is removably retained by frictional engagement inposition on the bulb 3 by the tension fingers 6. Within the shield 5 iscontained the refracting lens 7 which is retained in position by thelugs 8 and the depressed portion 9.

In the modification as shown in Figs. 5 and 6, the lens is containedwithin a substantially hemi-cylindrical shield 9 by means of lugs 10.The spring clips 11 and 12 are welded or soldered to the said shield 9in opposing relationship to each other and are retained on the lightbulb 3w by frictional engagement.

In Fig. 7 is shown a further modification in which no shield is employedand in which the lens is held in position on the light bulb by means ofopposed spring clips 13 (only one of which is visible in this view)molded into the glass of the lens.

- serves to absorb and reflect rays of light which otherwise might beprojected in undesirable directions.

Referring again to Fig. 1, the circuit for the bulb 3, which includesthe conductors 15 and 16, has connected in series the rheostat 17 forcontrolling the intensity of the illumination. While it is coinmonpractice to in corporate resistance into the line. for the electricbulb, this resistance has been fixed and used for the benefit of thedriver of a vehicle. approaching from the opposite direction. Exhaustivetests have shown that a projector type lamp functioning at its maximumintensity does not produce the greatest visibility in variousatmospheric conditions, such as fog or rain, and that by makingprovlsions in the circuit forvarying the intensity of the illuminationit is possible to enjoy the greatest road visibility.

In the embodiment shown, I have provided a construction which willenable the lens and shield to be removed or replaced from or to the bulbwith great ease. 'This obviously is desirable when the bulb must bereplaced or on other occasions when it may be necessary to remove theshield and lens.

While I have shown and described various embodiments of the presentinvention, it will be apparent to those skilled in the art that manymodifications thereof may be made without departing from the spirit andscope of this invention, and, therefore, the same is to be limited onlyby the prior art and the scope of the appended claims.

I claim: V

1. A shield and lens in combination, said shield being provided with aplurality of opposin tension fingersfor detachably affixing the same .toan electric bulb and to retain said lens, said fingers having sulficienttension to retain the shield and lens in their affixed position with thelens in contact with the bulb, said shield extending forwardly beyondthe top of said lens.

2. A shield and lens for an electric bulb used in combination, theshield comprising a hollow cylinder, the internal surface of which istangent to said electric light bulb in a forward direction and having aplural-' ity of tension fingers extending from one end to embrace andfrictionally engage the surface of the electric bulb, the other endbeing out arcuately in'a manner to provide a hood over the up er portionof said lens which is retained within it by suitable lugs.

bulb in a forward direction and to which it is removably afiixed bymeans of a plurality of opposing tension fingers extending from itsrearward end and which embrace and are in frictional engagement with thesurface of the bulb, the opposite end of said shield being cut away inits lower portions but permitted to extend forward in its upper portionto provide a hood for said lens contained within it and retained inposition by lugs struck to suitable angles from the shield, saidinternal surface of the shield providing a reflecting surface which willredirect stray rays from the lens.

4. In a headlight the combination with a .concave reflector having anaxially aligned light bulb therein adjacent the focus of said reflector,of a lens adjacent said bulb and circumferentially adjustable relativethereto, said lens beingarranged to redirect to a forward directioninclined rays emitted from the bulb over a limited area, and a shieldadjacent and movable with said lens in the normal path of said inclinedrays and arranged to redirect any of said inclined rays misdirected bythe aberrations of said lens.

5. In a headlight the combination with a concave reflector having alight bulb therein adjacent the focus of said reflector, of a lensadjacent said bulb and circumferentially adjustable'in any directionthereon, said lens being arranged to redirect to a forward direction theinclined rays emitted from the bulb over a limited area,; and an'arcuate shield arranged to support said lens on said light bulb andmovable therewith, said arcuate shield extending forwardly of said lensand in the normal path of said inclined rays and arranged to interruptanyof said inclined rays misdirected by the aberrations of said lens.

In witness whereof, I have hereunto subscribed my name.

ADIEL Y. DODGE.

3. A shield and lens, in combination, to be used in cooperativerelationship with the electric light bulb of an automobile headlampconst-ruction, said shield comprising a hollow cylinder of metal,the internal surface of which is tangent to the electric light

